递等式计算(能巧算的要巧算)(1)14.5-4.5÷2.5;(2)(4+0.4)×2.5;(3)5.4×7.2+54×0.28;(4)

2025-05-15 21:18:41
推荐回答(1个)
回答1:

(1)14.5-4.5÷2.5
=14.5-1.8
=12.7

(2)(4+0.4)×2.5
=4×2.5+0.4×2.5
=10+1
=11


(3)5.4×7.2+54×0.28
=5.4×7.2+5.4×2.8
=5.4×(7.2+2.8)
=5.4×10
=54


(4)0.4×(1+0.5-1+0.5)÷0.02
=0.4×1÷0.02
=0.4÷0.02
=20


(5)2.5÷[(10.75-4.5)×0.4]
=2.5÷[6.25×0.4]
=2.5÷2.5
=1